The use of natural diamond in wear components, such as in cutting and grinding tools, is very old. In addition to extreme hardness, diamond's superlative thermal conductivity, thermal stability, and inertness are unsurpassed for wear applications. In recent times synthetic polycrystalline diamond films have been successfully produced, such as by chemical vapor deposition (CVD), and used commercially in wear applications. The synthetic diamond films can be deposited directly on the base of a wear component, for example as a thin film (generally defined as a film having a thickness of less than 20 microns), or produced separately, generally as a thick film, and mounted on the base of a wear component, such as by brazing.
Even exceedingly hard diamond surfaces have a limited wear life, and the wear life of synthetic diamond, which can vary considerably for different synthetic diamond material, is a key factor in the cost-effectiveness of a wear component. A number of factors are recognized as affecting the wear life of synthetic diamond. The presence of foreign matter, voids, and cracks are all usually deleterious to the wear resistance of diamond. In this context, foreign matter also includes carbon not possessing the diamond structure, such as graphite.
It is among the objects of the present invention to provide synthetic diamond having improved wear properties, an improved method of making such diamond, and a method of determining the suitability of synthetic diamond for wear applications.